20775143 has 4 divisors (see below), whose sum is σ = 21059808. Its totient is φ = 20490480.

The previous prime is 20775137. The next prime is 20775191. The reversal of 20775143 is 34157702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34157702 = 2 ⋅17078851.

It is a cyclic number.

It is not a de Polignac number, because 20775143 - 2⁴ = 20775127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20775103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142223 + ... + 142368.

It is an arithmetic number, because the mean of its divisors is an integer number (5264952).

Almost surely, 2^20775143 is an apocalyptic number.

20775143 is a deficient number, since it is larger than the sum of its proper divisors (284665).

20775143 is an equidigital number, since it uses as much as digits as its factorization.

20775143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284664.

The product of its (nonzero) digits is 5880, while the sum is 29.

The square root of 20775143 is about 4557.9757568465. The cubic root of 20775143 is about 274.9041781857.

The spelling of 20775143 in words is "twenty million, seven hundred seventy-five thousand, one hundred forty-three".